<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>骨架模板</title>

    <style>
        canvas {
            border: 1px solid black;
        }
    </style>
</head>

<body>
    <canvas id="tutorial" width="150" height="150">
    </canvas>
    <script>
        var canvas = document.getElementById('tutorial')
        var ctx = canvas.getContext('2d')
    </script>
</body>

</html>